Sorghum inbred PH2877MR

ABSTRACT

A novel sorghum variety designated PH2877MR and seed, plants and plant parts thereof are provided. Methods for producing a plant comprise crossing sorghum variety PH2877MR with another plant. Sorghum seed, plants and plant parts produced by crossing sorghum variety PH2877MR with another plant are described. Methods for producing a plant containing in its genetic material one or more traits introgressed into PH2877MR include one or both of backcross conversion and transformation. Hybrid sorghum seed, plants or plant parts produced by crossing the sorghum variety PH2877MR or a locus conversion of PH2877MR with another sorghum variety are disclosed.

BACKGROUND

One goal of plant breeding is to combine, in a single hybrid or variety,various desirable traits. For field crops, these traits may includeresistance to diseases and insects, resistance to heat and drought,reducing the time to crop maturity, greater yield, and better agronomicquality. Uniformity of plant characteristics such as germination andstand establishment, growth rate, maturity, plant height and fruit sizefacilitate mechanical harvesting. Traditional plant breeding through thedevelopment and use of inbred varieties facilitates the development ofnew and improved commercial crops.

SUMMARY

According to the present invention, there is provided a novel sorghumline designated PH2877MR. This invention relates to seed of sorghum linePH2877MR, to the plants of sorghum line PH2877MR, to plant parts ofsorghum line PH2877MR, and to processes for making a plant that comprisecrossing sorghum line PH2877MR with another plant. This invention alsorelates to processes for making a plant containing in its geneticmaterial one or more traits introgressed into PH2877MR through backcrossconversion and/or transformation, and to the seed, plant and plant artsproduced thereby. This invention further relates to a hybrid seed,plant, or plant part produced by crossing the line PH2877MR or a locusconversion of PH2877MR with another plant.

DETAILED DESCRIPTION

In the description and examples that follow, a number of terms are usedherein. In order to provide a clear and consistent understanding of thespecification and claims, including the scope to be given such terms,the following definitions are provided:

Anthracnose Resistance. This is a visual rating based on the number oflesions caused by anthracnose infection. A score of 9 would indicatelittle necrosis and a score of 1 would indicate plant death as a resultof anthracnose infection.

Bacterial Spot. Bacterial Spot is a disease characterized by small,irregularly shaped lesions on the leaves. Bacterial Spot Resistance israted on a scale of 1 to 9, with 1 being susceptible and 9 beingresistant.

Bacterial Streak. Bacterial Streak is a disease characterized by narrowyellow stripes on the leaves. Bacterial Streak Resistance is rated on ascale of 1 to 9, with 1 being susceptible and 9 being resistant.

Bacterial Stripe. Bacterial Stripe is a disease characterized by long,narrow red stripes on the leaves. Bacterial Stripe Resistance is ratedon a scale of 1 to 9, with 1 being susceptible and 9 being resistant.

Biotype C Greenbug Resistance. This is a visual rating based on theamount of necrosis on leaves and stems caused by biotype C greenbugfeeding. A score of 9 would indicate no leaf or stem damage as a resultof greenbug feeding.

Biotype E Greenbug Resistance. This is a visual rating based on plantseedlings ability to continue growing when infested with large numbersof biotype E greenbugs. A score of 9 indicates normal growth and a scoreof 1 indicates seedling death.

Charcoal Rot. Charcoal Rot is a disease characterized by rotting of theroots and stalks. Charcoal Rot Resistance is rated on a scale of 1 to 9,with 1 being susceptible and 9 being resistant.

Chinch Bug Resistance. This is a visual rating based on the plantsability to grow normally when infested with large numbers of chinchbugs. A score of 9 would indicate normal growth and a score of 1 wouldindicate severe plant stunting and death.

Crop Response to Herbicide. Rated as the visual difference betweensprayed and un-sprayed plants. A crop response of less than 30% means novisual difference, higher percentages means sprayed plants showed somedamage.

Days to Color. The days to color is the number of days required for aninbred line or hybrid to begin grain coloring from the time of planting.Coloring of the grain is correlated with physiological maturity, thusdays to color gives an estimate of the period required before a hybridis ready for harvest.

Days to Flower. The days to flower is the number of days required for aninbred line or hybrid to shed pollen from the time of planting.

Downy Mildew Resistance (Pathotypes 1, 3, and 6). This is a visualrating based on the percentage of downy mildew infected plants. A scoreof 9 indicates no infected plants. A score of 1 would indicate higherthan 50% infected plants. Ratings are made for infection by eachpathotype of the disease.

Drought Tolerance. This represents a rating for drought tolerance and isbased on data obtained under stress. It is based on such factors asyield, plant health, lodging resistance and stay green. A high scorewould indicate a hybrid tolerant to drought stress.

Dry Down. This represents the relative rate at which a plant will reachacceptable harvest moisture compared to other plants. A high scoreindicates a plant that dries relatively fast while a low score indicatesa plant that dries slowly.

Fusarium Root and Stalk Rot. Fusarium Root and Stalk Rot is a diseasecharacterized by rotting of the roots and stalks. Fusarium Root andStalk Rot Resistance is rated on a scale of 1 to 9, with 1 beingsusceptible and 9 being resistant.

Grain Mold. Grain Mold is characterized by the formation of mold onheads and grain. Grain Mold Resistance is rated on a scale of 1 to 9,with 1 being susceptible and 9 being resistant.

Gray Leaf Spot Resistance. This is a visual rating based on the numberof gray leaf spot lesions present on the leaves and stem of the plant. Ascore of 9 would indicate the presence of few lesions.

Head Exertion. This represents a rating for the length of the peduncleexposed between the base of the panicle (head) and the flag leaf of theplant. A high score indicates more distance between the flag leaf andthe sorghum head while a low score indicates a short distance betweenthe two. Head exertion facilitates ease of combine harvesting.

Head Smut Resistance (Races 1-5). This is a visual rating based on thepercentage of smut infected plants. A score of 9 would indicate noinfected plants and a score of 1 would indicate higher than 50% infectedplants. Ratings are made for each race of head smut.

Head Type. This represents a rating of the morphology of the sorghumpanicle (head). A high score indicates an open panicle caused by eithermore distance between panicle branches or longer panicle branches. A lowscore indicates a more compact panicle caused by shorter paniclebranches arranged more closely on the central rachis.

Leaf Burn Resistance. This is a visual rating based on the amount oftissue damage caused by exposure to insecticide sprays. A score of 9would indicate minor leaf spotting and a score of 1 would indicate leafdeath as a result of contact with insecticide spray.

Locus Conversion (Also called a Trait Conversion): A locus conversionrefers to a modified plant within a variety that retains the overallgenetics of the variety and further includes a locus with one or morespecific desired traits, and otherwise has the same, essentially thesame, all or essentially all of the physiological and morphologicalcharacteristics of the variety, such as listed in Table 1. Traits can bedirected to, for example, modified grain, male sterility, insectcontrol, disease control or herbicide tolerance. Traits can be mutantgenes, transgenic sequences or native traits. A single locus conversionrefers to plants within a variety that have been modified in a mannerthat retains the overall genetics of the variety and include a singlelocus with one or more specific desired traits. A single locusconversion can include at least or about 1, 2, 3, 4 or 5 traits and lessthan or about 15, 10, 9, 8, 7 or 6 traits. A locus converted plant caninclude, for example, at least or about 1, 2 or 3 and less than or about20, 15, 10, 9, 8, 7, 6, or 5 modified loci while still retaining theoverall genetics of the variety and otherwise having essentially thesame, the same, all or essentially all of the physiological andmorphological characteristics of the variety, such as listed in Table 1.The total number of traits at one or more locus conversions can be, forexample, at least or about 1, 2, 3, 4 or 5 and less than or about 25,20, 15, 10, 9, 8, 7 or 6. Examples of single locus conversions includemutant genes, transgenes and native traits finely mapped to a singlelocus. Traits may be introduced by transformation, backcrossing, or acombination of both.

Maize Dwarf Mosaic Virus Resistance. This is a visual rating based onthe percentage of sorghum plants showing symptoms of virus infection. Ascore of 9 would indicate no plants with virus symptoms and a 1 wouldindicate a high percentage of plants showing symptoms of virus infectionsuch as stunting, red leaf symptoms or leaf mottling.

Midge Resistance. This is a visual rating based on the percentage ofseed set in the panicle in the presence of large numbers of midgeadults. A score of 9 would indicate near normal seed set and a score of1 would indicate no seed set in the head due to midge damage.

Moisture. The moisture is the actual percentage moisture of the grain atharvest.

Percent Yield. The percent yield is the yield obtained from the hybridin terms of percent of the mean for the experiment in which it wasgrown.

Plant: As used herein, the term “plant” includes reference to animmature or mature whole plant, including a plant from which seed orgrain has been removed.

Plant Height. This is a measure of the average height of the hybrid fromthe ground to the tip of the panicle and is measured in inches.

Plant Part: As used herein, the term “plant part” includes leaves,stems, roots, seed, grain, kernels, panicles, embryo, pollen, ovules,flowers, stalks, root tips, anthers, pericarp, protoplasts, tissue,plant calli, cells and the like. In some embodiments the plant partcontains at least one cell of sorghum variety PH2877MR.

Predicted RM. This trait, predicted relative maturity (RM), for a hybridis based on the number of days required for an inbred line or hybrid toshed pollen from the time of planting. The relative maturity rating isbased on a known set of checks and utilizes standard linear regressionanalyses.

Puccinia (Rust) Resistance. This is a visual rating based on the numberof rust pustules present on the leaves and stem of the plant. A score of9 would indicate the presence of few rust pustules.

RM to Color. This trait for a hybrid is based on the number of daysrequired for a hybrid to begin to show color development in the grainfrom the time of planting. The relative maturity rating is based on aknown set of checks and utilizes standard linear regression analyses.

Root Lodging. This represents a rating of the percentage of plants thatdo not root lodge, i.e. those that lean from the vertical axis at anapproximate 30 degree angle or greater without stalk breakage areconsidered to be root lodged. This is a relative rating of a hybrid toother hybrids for standability. Root lodging is rated on a scale of 1 to9, with 1 indicating greater than 50% lodged plants and 9 indicating nolodged plants.

Sales Appearance. This represents a rating of the acceptability of thehybrid in the market place. It is a complex score including such factorsas hybrid uniformity, appearance of yield, grain texture, grain colorand general plant health. A high score indicates the hybrid would bereadily accepted based on appearance only. A low score indicates hybridacceptability to be marginal based on appearance only.

Salt Tolerance. This represents a rating of the plants ability to grownormally in soils having high sodium salt content. This is a relativerating of a hybrid to other hybrids for normal growth.

Selection Index. The selection index gives a single measure of thehybrid's worth based on information for up to five traits. A sorghumbreeder may utilize his or her own set of traits for the selectionindex. Two of the traits that are almost always included are yield anddays to flower (maturity). The selection index data presented in thetables in the specification represent the mean values averaged acrosstesting stations.

Sooty Stripe. Sooty Stripe is a disease characterized by elongate,elliptical lesions on the leaves. Sooty Stripe Resistance is rated on ascale of 1 to 9, with 1 being susceptible and 9 being resistant.

Stalk Lodging. This represents a rating of the percentage of plants thatdo not stalk lodge, i.e. stalk breakage above the ground caused bynatural causes. This is a relative rating of a hybrid to other hybridsfor standability. Stalk lodging is rated on a scale of 1 to 9, with 1indicating greater than 50% lodged plants and 9 indicating no lodgedplants.

Stay Green. Stay green is the measure of plant health near the time ofharvest. A high score indicates better late-season plant health.

Test Weight. This is the measure of the weight of the grain in poundsfor a given volume (bushel) adjusted for percent moisture.

Weathering. This represents a rating of how well the exposed grains areable to retain normal seed quality when exposed to normal weatherhazards and surface grain molds.

Yield (cwt/acre). The yield in cwt/acre is the actual yield of the grainat harvest adjusted to 13% moisture.

Yield/RM. This represents a rating of a hybrid yield compared to otherhybrids of similar maturity or RM. A high score would indicate a hybridwith higher yield than other hybrids of the same maturity.

Yield Under Stress. This is a rating of the plants ability to producegrain under heat and drought stress conditions. A score of 9 wouldindicate near normal growth and grain yield and a score of 1 wouldindicate substantial yield reduction due to stress.

Zonate Leaf Spot Resistance. This is a visual rating based on the numberof zonate leaf spot lesions present on the leaves and stem of the plant.A score of 9 would indicate the presence of few lesions.

Field crops are bred through techniques that take advantage of theplant's method of pollination. A plant is self-pollinating if pollenfrom one flower is transferred to the same or another flower of the sameplant. A plant is cross-pollinated if the pollen comes from a flower ona different plant.

Plants that have been self-pollinated and selected for type for manygenerations become homozygous at almost all gene loci and produce auniform population of true breeding progeny. A cross between twohomozygous plants from differing backgrounds or two homozygous linesproduce a uniform population of hybrid plants that may be heterozygousfor many gene loci. A cross of two plants that are each heterozygous ata number of gene loci will produce a population of hybrid plants thatdiffer genetically and will not be uniform.

Sorghum plants (Sorghum bicolor L. Moench) are bred in most cases byself-pollination techniques. With the incorporation of male sterility(either genetic or cytoplasmic) cross pollination breeding techniquescan also be utilized. Sorghum has both male and female parts in the sameflower located in the panicle. The flowers are usually in pairs on thepanicle branches. Natural pollination occurs in sorghum when anthers(male flowers) open and pollen falls onto receptive stigma (femaleflowers). Because of the close proximity of male (anthers) and female(stigma) in the panicle, self-pollination is very high (average 94%).Cross pollination may occur when wind or convection currents move pollenfrom the anthers of one plant to receptive stigma on another plant.Cross pollination is greatly enhanced with incorporation of malesterility which renders male flowers nonviable without affecting thefemale flowers. Successful pollination in the case of male sterileflowers requires cross pollination.

Sorghum is in the same family as maize and has a similar growth habit,but with more tillers and a more extensively branched root system.Sorghum is more drought resistant and heat-tolerant than maize. Itrequires an average temperature of at least 25° C. to produce maximumyields. Sorghum's ability to thrive with less water than maize may bedue to its ability to hold water in its foliage better than maize.Sorghum has a waxy coating on its leaves and stems which helps to keepwater in the plant even in intense heat. Wild species of sorghum tend togrow to a height of 1.5 to 2 meters; to improve harvestability, dwarfinggenes have been selected in cultivated varieties and hybrids such thatmost cultivated varieties and hybrids grow to 60 and 120 cm tall.

Inbred Development

The development of sorghum hybrids requires the development ofhomozygous inbred lines, the crossing of these lines, and the evaluationof the crosses. Pedigree breeding methods, and to a lesser extentpopulation breeding methods, are used to develop inbred lines frombreeding populations. Breeding programs combine desirable traits fromtwo or more inbred lines into breeding pools from which new inbred linesare developed by selfing and selection of desired phenotypes. The newinbreds are crossed with other inbred lines and the hybrids from thesecrosses are evaluated to determine which have commercial potential.

Pedigree breeding starts with the crossing of two genotypes, each ofwhich may have one or more desirable characteristics that is lacking inthe other or which complement the other. If the two original parents donot provide all of the desired characteristics, other sources can beincluded in the breeding population. In the pedigree method, superiorplants are selfed and selected in successive generations. In thesucceeding generations the heterozygous condition gives way tohomogeneous lines as a result of self-pollination and selection.Typically, in the pedigree method of breeding five or more generationsof selfing and selection is practiced. F₁ to F₂; F₂ to F₃; F₃ to F₄, F₄to F₅, etc.

Backcrossing can be used to improve an inbred line. Backcrossingtransfers a specific desirable trait from one inbred or source to aninbred that lacks that trait. This can be accomplished for example byfirst crossing a superior inbred (A) (recurrent parent) to a donorinbred (non-recurrent parent), which carries the appropriate genes(s)for the trait in question. The progeny of this cross is then mated backto the superior recurrent parent (A) followed by selection in theresultant progeny for the desired trait to be transferred from thenon-recurrent parent. After five or more backcross generations withselection for the desired trait, the progeny will be heterozygous forloci controlling the characteristic being transferred, but will be likethe superior parent for most or almost all other genes. The lastbackcross generation would be selfed to give pure breeding progeny forthe gene(s) being transferred.

Controlling Self-Pollination

Sorghum varieties are mainly self-pollinated; therefore,self-pollination of the parental varieties must be controlled to makehybrid development feasible. A pollination control system and effectivetransfer of pollen from one parent to the other offers improved plantbreeding and an effective method for producing hybrid seed and plants.For example, the milo or A₁ cytoplasmic male sterility (CMS) system,developed via a cross between milo and kafir cultivars, is one of themost frequently used CMS systems in hybrid sorghum production (StephensJ C & Holland P F, Cytoplasmic Male Sterility for Hybrid Sorghum SeedProduction, Agron. J. 46:20-23 (1954)). Other CMS systems for sorghuminclude, but are not limited to, A₂, isolated from IS 12662c (Schertz KF, Registration of A ₂ T _(x) 2753 and BT _(x) 2753 Sorghum Germplasm,Crop Sci. 17: 983 (1977)), A₃, isolated from IS 1112c or converted Nilwa(Quinby J R, Interactions of Genes and Cytoplasms in Male-Sterility inSorghums, Proc. 35th Corn Sorghum Res. Conf. Am. Seed Trade Assoc.Chicago, Ill., pp. 5-8 (1980)), A₄, isolated from IS 7920c (Worstell etal, Relationship among Male-Sterility Inducing Cytoplasms of Sorghum,Crop Sci. 24:186-189 (1984)).

In developing improved new sorghum hybrid varieties, breeders may use aCMS plant as the female parent. In using these plants, breeders attemptto improve the efficiency of seed production and the quality of the F₁hybrids and to reduce the breeding costs. When hybridization isconducted without using CMS plants, it is more difficult to obtain andisolate the desired traits in the progeny (F₁ generation) because theparents are capable of undergoing both cross-pollination andself-pollination. If one of the parents is a CMS plant that is incapableof producing pollen, only cross pollination will occur. By eliminatingthe pollen of one parental variety in a cross, a plant breeder isassured of obtaining hybrid seed of uniform quality, provided that theparents are of uniform quality and the breeder conducts a single cross.

In one instance, production of F₁ hybrids includes crossing a CMS femaleparent with a pollen-producing male parent. To reproduce effectively,however, the male parent of the F₁ hybrid must have a fertility restorergene (Rf gene). The presence of an Rf gene means that the F₁ generationwill not be completely or partially sterile, so that eitherself-pollination or cross pollination may occur. Self-pollination of theF₁ generation to produce several subsequent generations is important toensure that a desired trait is heritable and stable and that a newvariety has been isolated.

Promising advanced breeding lines commonly are tested and compared toappropriate standards in environments representative of the commercialtarget area(s). The best lines are candidates for new commercial lines;and those still deficient in a few traits may be used as parents toproduce new populations for further selection.

Hybrid Development

A hybrid sorghum variety is the cross of two inbred lines, each of whichmay have one or more desirable characteristics lacked by the other orwhich complement the other. The hybrid progeny of the first generationis designated F₁. In the development of hybrids only the F₁ hybridplants are sought. The F₁ hybrid is more vigorous than its inbredparents. This hybrid vigor, or heterosis, can be manifested in manyways, including increased vegetative growth and increased yield.

The development of a hybrid sorghum variety involves five steps: (1) theformation of “restorer” and “non-restorer” germplasm pools; (2) theselection of superior plants from various “restorer” and “non-restorer”germplasm pools; (3) the selfing of the superior plants for severalgenerations to produce a series of inbred lines, which althoughdifferent from each other, each breed true and are highly uniform; (4)the conversion of inbred lines classified as non-restorers tocytoplasmic male sterile (CMS) forms, and (5) crossing the selectedcytoplasmic male sterile (CMS) inbred lines with selected fertile inbredlines (restorer lines) to produce the hybrid progeny (F₁).

Because sorghum is normally a self-pollinated plant and because bothmale and female flowers are in the same panicle, large numbers of hybridseed can only be produced by using cytoplasmic male sterile (CMS)inbreds. Flowers of the CMS inbred are fertilized with pollen from amale fertile inbred carrying genes which restore male fertility in thehybrid (F₁) plants. An important consequence of the homozygosity andhomogeneity of the inbred lines is that the hybrid between any twoinbreds will always be the same. Once the inbreds that produce the besthybrid have been identified, the hybrid seed can be reproducedindefinitely as long as the homogeneity of the inbred parent ismaintained.

A single cross hybrid is produced when two inbred lines are crossed toproduce the F₁ progeny. Much of the hybrid vigor exhibited by F₁ hybridsis lost in the next generation (F₂). Consequently, seed from hybridvarieties is not used for planting stock.

Hybrid grain sorghum can be produced using wind to move the pollen.Alternating strips of the cytoplasmic male sterile inbred (female) andthe male fertile inbred (male) are planted in the same field. Wind movesthe pollen shed by the male inbred to receptive stigma on the female.Providing that there is sufficient isolation from sources of foreignsorghum pollen, the stigma of the male sterile inbred (female) will befertilized only with pollen from the male fertile inbred (male). Theresulting seed, born on the male sterile (female) plants is thereforehybrid and will form hybrid plants that have full fertility restored.

Genotypic Characteristics of Variety PH2877MR

In addition to phenotypic observations, a plant can also be described oridentified by its genotype. The genotype of a plant can be characterizedthrough a genetic marker profile. Genetic marker profiles can beobtained by techniques such as Restriction Fragment Length Polymorphisms(RFLPs), Randomly Amplified Polymorphic DNAs (RAPDs), Arbitrarily PrimedPolymerase Chain Reaction (AP-PCR), DNA Amplification Fingerprinting(DAF), Sequence Characterized Amplified Regions (SCARs), AmplifiedFragment Length Polymorphisms (AFLPs), Simple Sequence Repeats (SSRs)which are also referred to as Microsatellites, and Single NucleotidePolymorphisms (SNPs).

Particular markers used for these purposes may include any type ofmarker and marker profile which provides a means of distinguishingvarieties. A genetic marker profile can be used, for example, toidentify plants of the same variety or related varieties or to determineor validate a pedigree. In addition to being used for identification ofsorghum variety PH2877MR and its plant parts, the genetic marker profileis also useful in developing a locus conversion of PH2877MR.

Methods of isolating nucleic acids from sorghum plants and methods forperforming genetic marker profiles using SNP and SSR polymorphisms arewell known in the art. SNPs are genetic markers based on a polymorphismin a single nucleotide. A marker system based on SNPs can be highlyinformative in linkage analysis relative to other marker systems in thatmultiple alleles may be present.

A method comprising isolating nucleic acids, such as DNA, from a plant,a plant part, plant cell or a seed of the sorghum plants disclosedherein is provided. The method can include mechanical, electrical and/orchemical disruption of the plant, plant part, plant cell or seed,contacting the disrupted plant, plant part, plant cell or seed with abuffer or solvent, to produce a solution or suspension comprisingnucleic acids, optionally contacting the nucleic acids with aprecipitating agent to precipitate the nucleic acids, optionallyextracting the nucleic acids, and optionally separating the nucleicacids such as by centrifugation or by binding to beads or a column, withsubsequent elution, or a combination thereof. If DNA is being isolated,an RNase can be included in one or more of the method steps. The nucleicacids isolated can comprise all or substantially all of the genomic DNAsequence, all or substantially all of the chromosomal DNA sequence orall or substantially all of the coding sequences (cDNA) of the plant,plant part, or plant cell from which they were isolated. The amount andtype of nucleic acids isolated may be sufficient to permit whole genomesequencing of the plant from which they were isolated or chromosomalmarker analysis of the plant from which they were isolated.

The methods can be used to produce nucleic acids from the plant, plantpart, seed or cell, which nucleic acids can be, for example, analyzed toproduce data. The data can be recorded. The nucleic acids from thedisrupted cell, the disrupted plant, plant part, plant cell or seed orthe nucleic acids following isolation or separation can be contactedwith primers and nucleotide bases, and/or a polymerase to facilitate PCRsequencing or marker analysis of the nucleic acids. In some examples,the nucleic acids produced can be sequenced or contacted with markers toproduce a genetic profile, a molecular profile, a marker profile, ahaplotype, or any combination thereof. In some examples, the geneticprofile or nucleotide sequence is recorded on a computer readablemedium. In other examples, the methods may further comprise using thenucleic acids produced from plants, plant parts, plant cells or seeds ina plant breeding program, for example in making crosses, selectionand/or advancement decisions in a breeding program. Crossing includesany type of plant breeding crossing method, including but not limited tocrosses to produce hybrids, outcrossing, selfing, backcrossing, locusconversion, introgression and the like. Favorable genotypes and ormarker profiles, optionally associated with a trait of interest, may beidentified by one or more methodologies. In some examples one or moremarkers are used, including but not limited to AFLPs, RFLPs, ASH, SSRs,SNPs, indels, padlock probes, molecular inversion probes, microarrays,sequencing, and the like. In some methods, a target nucleic acid isamplified prior to hybridization with a probe. In other cases, thetarget nucleic acid is not amplified prior to hybridization, such asmethods using molecular inversion probes. In some examples, the genotyperelated to a specific trait is monitored, while in other examples, agenome-wide evaluation including but not limited to one or more ofmarker panels, library screens, association studies, microarrays, genechips, expression studies, or sequencing such as whole-genomeresequencing and genotyping-by-sequencing (GBS) may be used. In someexamples, no target-specific probe is needed, for example by usingsequencing technologies, including but not limited to next-generationsequencing methods (see, for example, Metzker (2010) Nat Rev Genet11:31-46; and, Egan et al. (2012) Am J Bot 99:175-185) such assequencing by synthesis (e.g., Roche 454 pyrosequencing, Illumina GenomeAnalyzer, and Ion Torrent PGM or Proton systems), sequencing by ligation(e.g., SOLiD from Applied Biosystems, and Polnator system from AzcoBiotech), and single molecule sequencing (SMS or third-generationsequencing) which eliminate template amplification (e.g., Helicossystem, and PacBio RS system from Pacific BioSciences). Furthertechnologies include optical sequencing systems (e.g., Starlight fromLife Technologies), and nanopore sequencing (e.g., GridION from OxfordNanopore Technologies). Each of these may be coupled with one or moreenrichment strategies for organellar or nuclear genomes in order toreduce the complexity of the genome under investigation via PCR,hybridization, restriction enzyme, and expression methods. In someexamples, no reference genome sequence is needed in order to completethe analysis. Variety PH2877MR and its plant parts can be identifiedthrough a molecular marker profile. Such plant parts may be eitherdiploid or haploid. The plant part includes at least one cell of theplant from which it was obtained, such as a diploid cell, a haploid cellor a somatic cell. Also provided are plants and plant partssubstantially benefiting from the use of variety PH2877MR in theirdevelopment, such as variety PH2877MR comprising a locus conversion.

Locus Conversions of Sorghum Line PH2877MR

PH2877MR represents a new base genetic line into which a new locus ortrait may be introduced. Direct transformation and backcrossingrepresent two important methods that can be used to accomplish such anintrogression. The term locus conversion is used to designate theproduct of such an introgression.

To select and develop a superior hybrid, it is necessary to identify andselect genetically unique individuals that occur in a segregatingpopulation. The segregating population is the result of a combination ofcrossover events plus the independent assortment of specificcombinations of alleles at many gene loci that results in specific andunique genotypes. Once such a variety is developed its value to societyis substantial since it is important to advance the germplasm base as awhole in order to maintain or improve traits such as yield, diseaseresistance, pest resistance and plant performance in extreme weatherconditions. Locus conversions are routinely used to add or modify one ora few traits of such a line and this further enhances its value andusefulness to society.

Backcrossing can be used to improve inbred varieties and a hybridvariety which is made using those inbreds. Backcrossing can be used totransfer a specific desirable trait from one variety, the donor parent,to an inbred called the recurrent parent which has overall goodagronomic characteristics yet that lacks the desirable trait. Thistransfer of the desirable trait into an inbred with overall goodagronomic characteristics can be accomplished by first crossing arecurrent parent to a donor parent (non-recurrent parent). The progenyof this cross is then mated back to the recurrent parent followed byselection in the resultant progeny for the desired trait to betransferred from the non-recurrent parent.

Traits may be used by those of ordinary skill in the art to characterizeprogeny. Traits are commonly evaluated at a significance level, such asa 1%, 5% or 10% significance level, when measured in plants grown in thesame environmental conditions. For example, a locus conversion ofPH2877MR may be characterized as having essentially the same phenotypictraits as PH2877MR. The traits used for comparison may be those traitsshown in Table 1. Molecular markers can also be used during the breedingprocess for the selection of qualitative traits. For example, markerscan be used to select plants that contain the alleles of interest duringa backcrossing breeding program. The markers can also be used to selectfor the genome of the recurrent parent and against the genome of thedonor parent. Using this procedure can minimize the amount of genomefrom the donor parent that remains in the selected plants.

A locus conversion of PH2877MR will retain the genetic integrity ofPH2877MR. A locus conversion of PH2877MR will comprise at least 92%,93%, 94%, 95%, 96%, 97%, 98% or 99% of the base genetics of PH2877MR.For example, a locus conversion of PH2877MR can be developed when DNAsequences are introduced through backcrossing (Hallauer et al., 1988),with a parent of PH2877MR utilized as the recurrent parent. Bothnaturally occurring and transgenic DNA sequences may be introducedthrough backcrossing techniques. A backcross conversion may produce aplant with a locus conversion in at least one or more backcrosses,including at least 2 crosses, at least 3 crosses, at least 4 crosses, atleast 5 crosses and the like. Molecular marker assisted breeding orselection may be utilized to reduce the number of backcrosses necessaryto achieve the backcross conversion. For example, see Openshaw, S. J. etal., Marker-assisted Selection in Backcross Breeding. In: ProceedingsSymposium of the Analysis of Molecular Data, August 1994, Crop ScienceSociety of America, Corvallis, Oreg., where it is demonstrated that abackcross conversion can be made in as few as two backcrosses. A locusconversion of PH2877MR can be determined through the use of a molecularprofile. A locus conversion of PH2877MR would have 92%, 93%, 94%, 95%,96%, 97%, 98% or 99% of the molecular markers, or molecular profile, ofPH2877MR. Examples of molecular markers that could be used to determinethe molecular profile include Restriction Fragment Length Polymorphisms(RFLP), Polymerase Chain Reaction (PCR) analysis, and Simple SequenceRepeats (SSR), and Single Nucleotide Polymorphisms (SNPs).

Genetic Modification and Transformation of Sorghum Line PH2877MR

Transgenes, genetic editing or modification and transformation methodsfacilitate engineering of the genome of plants to contain and expressheterologous genetic elements, such as foreign genetic elements, oradditional copies of endogenous elements, or modified versions of nativeor endogenous genetic elements in order to alter at least one trait of aplant in a specific manner. Any sequences, such as DNA, whether from adifferent species or from the same species, which have been stablyinserted into a genome using transformation are referred to hereincollectively as “transgenes” and/or “transgenic events”. Transgenes canbe moved from one genome to another using breeding techniques which mayinclude crossing, backcrossing or double haploid production. In someembodiments, a transformed variant of PH2877MR may comprise at least onetransgene or genetic modification but could contain at least 1, 2, 3, 4,5, 6, 7, 8, 9, 10 transgenes or genetic modifications and no more than15, 14, 13, 12, 11, 10, 9, 8, 7, 6, 5, 4, 3, or 2 transgenes or geneticmodifications. Transformed versions of the claimed variety PH2877MR aswell as hybrid combinations containing and inheriting the transgenethereof are provided. F₁ hybrid seed are provided which are produced bycrossing a different plant with variety PH2877MR comprising a transgeneintroduced into variety PH2877MR by backcrossing or genetictransformation and is inherited by the F₁ hybrid seed.

Numerous methods for plant transformation have been developed, includingbiological and physical plant transformation protocols. See, forexample, Miki et al., “Procedures for Introducing Foreign DNA intoPlants” in Methods in Plant Molecular Biology and Biotechnology, Glick,B. R. and Thompson, J. E. Eds. (CRC Press, Inc., Boca Raton, 1993) pages67-88 and Armstrong, “The First Decade of Maize Transformation: A Reviewand Future Perspective” (Maydica 44:101-109, 1999). In addition,expression vectors and in vitro culture methods for plant cell or tissuetransformation and regeneration of plants are available. See, forexample, Gruber et al., “Vectors for Plant Transformation” in Methods inPlant Molecular Biology and Biotechnology, Glick, B. R. and Thompson, J.E. Eds. (CRC Press, Inc., Boca Raton, 1993) pages 89-119.

In general, methods to transform, modify, edit or alter plant endogenousgenomic DNA include altering the plant native DNA sequence or apre-existing transgenic sequence including regulatory elements, codingand non-coding sequences. These methods can be used, for example, totarget nucleic acids to pre-engineered target recognition sequences inthe genome. Such pre-engineered target sequences may be introduced bygenome editing or modification. As an example, a genetically modifiedplant variety is generated using “custom” or engineered endonucleasessuch as meganucleases produced to modify plant genomes (see e.g., WO2009/114321; Gao et al. (2010) Plant Journal 1:176-187). Anothersite-directed engineering method is through the use of zinc fingerdomain recognition coupled with the restriction properties ofrestriction enzyme. See e.g., Urnov, et al., (2010) Nat Rev Genet.11(9):636-46; Shukla, et al., (2009) Nature 459 (7245):437-41. Atranscription activator-like (TAL) effector-DNA modifying enzyme (TALEor TALEN) is also used to engineer changes in plant genome. See e.g.,US20110145940, Cermak et al., (2011) Nucleic Acids Res. 39(12) and Bochet al., (2009), Science 326(5959): 1509-12. Site-specific modificationof plant genomes can also be performed using the bacterial type IICRISPR (clustered regularly interspaced short palindromic repeats)/Cas(CRISPR-associated) system. See e.g., Belhaj et al., (2013), PlantMethods 9: 39; The Cas9/guide RNA-based system allows targeted cleavageof genomic DNA guided by a customizable small noncoding RNA in plants(see e.g., WO 2015026883A1).

Plant transformation methods may involve the construction of anexpression vector. Such a vector comprises a DNA sequence that containsa gene under the control of or operatively linked to a regulatoryelement, for example a promoter. The vector may contain one or moregenes and one or more regulatory elements.

A transgenic event which has been engineered into a particular sorghumplant using transformation techniques, could be moved into another lineusing traditional breeding techniques that are well known in the plantbreeding arts. For example, a backcrossing approach could be used tomove a transgene from a transformed sorghum plant to an elite inbredline and the resulting progeny would comprise a transgene. Also, if aninbred line was used for the transformation then the transgenic plantscould be crossed to a different line in order to produce a transgenichybrid sorghum plant. As used herein, “crossing” can refer to a simple Xby Y cross, or the process of backcrossing, depending on the context.Various genetic elements can be introduced into the plant genome usingtransformation. These elements include but are not limited to genes;coding sequences; inducible, constitutive, and tissue specificpromoters; enhancing sequences; and signal and targeting sequences. Forexample, see, U.S. Pat. No. 6,118,055.

With transgenic plants according to the present discovery, a foreignprotein can be produced in commercial quantities. Thus, techniques forthe selection and propagation of transformed plants, which are wellunderstood in the art, yield a plurality of transgenic plants which areharvested in a conventional manner, and a foreign protein then can beextracted from a tissue of interest or from total biomass. Proteinextraction from plant biomass can be accomplished by known methods whichare discussed, for example, by Heney and Orr, (1981) Anal. Biochem.114:92-96.

A genetic map can be generated, primarily via conventional RestrictionFragment Length Polymorphisms (RFLP), Polymerase Chain Reaction (PCR)analysis, and Simple Sequence Repeats (SSR), and Single NucleotidePolymorphisms (SNPs), which identifies the approximate chromosomallocation of the integrated DNA molecule coding for the foreign protein.For exemplary methodologies in this regard, see, Glick and Thompson,METHODS IN PLANT MOLECULAR BIOLOGY AND BIOTECHNOLOGY 269-284 (CRC Press,Boca Raton, 1993). Map information concerning chromosomal location isuseful for proprietary protection of a subject transgenic plant. Ifunauthorized propagation is undertaken and crosses made with othergermplasm, the map of the integration region can be compared to similarmaps for suspect plants, to determine if the latter have a commonparentage with the subject plant. Map comparisons would involvehybridizations, RFLP, PCR, SSR, SNP, and sequencing, all of which areconventional techniques.

Likewise, by means of the present discovery, plants can be geneticallyengineered to express various phenotypes of agronomic interest.Exemplary transgenes implicated in this regard include, but are notlimited to, those categorized below.

1. Genes that create a site for site specific DNA integration.

This includes the introduction of FRT sites that may be used in theFLP/FRT system and/or Lox sites that may be used in the Cre/Loxp system.For example, see, Lyznik, et al., (2003) “Site-Specific Recombinationfor Genetic Engineering in Plants”, Plant Cell Rep 21:925-932 and WO99/25821, which are hereby incorporated by reference. Other systems thatmay be used include the Gin recombinase of phage Mu (Maeser, et al.,1991), the Pin recombinase of E. coli (Enomoto, et al., 1983), and theR/RS system of the pSR1 plasmid (Araki, et al., 1992).

2. Genes that affect abiotic stress resistance (including but notlimited to flowering, panicle/glume and seed development, enhancement ofnitrogen utilization efficiency, altered nitrogen responsiveness,drought resistance or tolerance, cold resistance or tolerance, and saltresistance or tolerance) and increased yield under stress.

For example, see, WO 00/73475 where water use efficiency is alteredthrough alteration of malate; U.S. Pat. Nos. 5,892,009, 5,965,705,5,929,305, 5,891,859, 6,417,428, 6,664,446, 6,706,866, 6,717,034,6,801,104, WO2000060089, WO2001026459, WO2001035725, WO2001034726,WO2001035727, WO2001036444, WO2001036597, WO2001036598, WO2002015675,WO2002017430, WO2002077185, WO2002079403, WO2003013227, WO2003013228,WO2003014327, WO2004031349, WO2004076638, WO9809521 and WO9938977describing genes, including CBF genes and transcription factorseffective in mitigating the negative effects of freezing, high salinity,and drought on plants, as well as conferring other positive effects onplant phenotype; US Patent Application Publication Number 2004/0148654and WO01/36596 where abscisic acid is altered in plants resulting inimproved plant phenotype such as increased yield and/or increasedtolerance to abiotic stress; WO2000/006341, WO04/090143, U.S. patentapplication Ser. Nos. 10/817,483 and 09/545,334 where cytokininexpression is modified resulting in plants with increased stresstolerance, such as drought tolerance, and/or increased yield. Also seeWO0202776, WO03052063, JP2002281975, U.S. Pat. No. 6,084,153, WO0164898,U.S. Pat. Nos. 6,177,275 and 6,107,547 (enhancement of nitrogenutilization and altered nitrogen responsiveness). For ethylenealteration, see, US Patent Application Publication Numbers 2004/0128719,2003/0166197 and WO200032761. For plant transcription factors ortranscriptional regulators of abiotic stress, see e.g., US PatentApplication Publication Number 2004/0098764 or US Patent ApplicationPublication Number 2004/0078852.

Other genes and transcription factors that affect plant growth andagronomic traits such as yield, flowering, plant growth and/or plantstructure, can be introduced or introgressed into plants, see, e.g.,WO97/49811 (LHY), WO98/56918 (ESD4), WO97/10339 and U.S. Pat. No.6,573,430 (TFL), U.S. Pat. No. 6,713,663 (FT), WO96/14414 (CON),WO96/38560, WO01/21822 (VRN1), WO00/44918 (VRN2), WO99/49064 (GI),WO00/46358 (FRI), WO97/29123, U.S. Pat. Nos. 6,794,560, 6,307,126 (GAI),WO99/09174 (D8 and Rht), and WO2004076638 and WO2004031349(transcription factors).

3. Transgenes that confer or contribute to an altered graincharacteristic, such as:

-   -   A. Altered phosphate content, for example, by the        -   (1) Introduction of a phytase-encoding gene would enhance            breakdown of phytate, adding more free phosphate to the            transformed plant. For example, see, Van Hartingsveldt, et            al., Gene 127:87 (1993), for a disclosure of the nucleotide            sequence of an Aspergillus niger phytase gene.        -   (2) Up-regulation of a gene that reduces phytate content.            For example, this could be accomplished, by cloning and then            re-introducing DNA associated with one or more of the            alleles, such as the LPA alleles, identified in mutants            characterized by low levels of phytic acid, such as in            Raboy, et al. (1990).    -   B. Altered fatty acids, for example, by down-regulation of        stearoyl-ACP desaturase to increase stearic acid content of the        plant. See Knultzon, et al., Proc. Natl. Acad. Sci. USA 89:2624        (1992).    -   C. Altered carbohydrates effected, for example, by altering a        gene for an enzyme that affects the branching pattern of starch,        a gene altering thioredoxin. (See, U.S. Pat. No. 6,531,648).        See, Shiroza, et al., (1988) J. Bacteriol 170:810 (nucleotide        sequence of Streptococcus mutans fructosyltransferase gene),        Steinmetz, et al., (1985) Mol. Gen. Genet. 200:220 (nucleotide        sequence of Bacillus subtilis levansucrase gene), Pen, et        al., (1992) Bio/Technology 10:292 (production of transgenic        plants that express Bacillus licheniformis alpha-amylase),        Elliot, et al., (1993) Plant Molec Biol 21:515 (nucleotide        sequences of tomato invertase genes), Søgaard, et al., (1993) J.        Biol. Chem. 268:22480 (site-directed mutagenesis of barley        alpha-amylase gene) and Fisher, et al., (1993) Plant Physiol        102:1045 (maize endosperm starch branching enzyme II), WO        99/10498 (improved digestibility and/or starch extraction        through modification of UDP-D-xylose 4-epimerase, Fragile 1 and        2, Ref1, HCHL, C4H), U.S. Pat. No. 6,232,529 (method of        producing high oil seed by modification of starch levels (AGP)).        The fatty acid modification genes mentioned above may also be        used to affect starch content and/or composition through the        interrelationship of the starch and oil pathways.    -   D. Altered antioxidant content or composition, such as        alteration of tocopherol or tocotrienols. For example, see, U.S.        Pat. No. 6,787,683, US Patent Application Publication Number        2004/0034886 and WO 00/68393 involving the manipulation of        antioxidant levels through alteration of a phytl prenyl        transferase (ppt), WO 03/082899 through alteration of a        homogentisate geranyl geranyl transferase (hggt).    -   E. Altered essential seed amino acids. For example, see, U.S.        Pat. No. 6,127,600 (method of increasing accumulation of        essential amino acids in seeds), U.S. Pat. No. 6,080,913 (binary        methods of increasing accumulation of essential amino acids in        seeds), U.S. Pat. No. 5,990,389 (high lysine), WO99/40209        (alteration of amino acid compositions in seeds), WO99/29882        (methods for altering amino acid content of proteins), U.S. Pat.        No. 5,850,016 (alteration of amino acid compositions in seeds),        WO98/20133 (proteins with enhanced levels of essential amino        acids), U.S. Pat. No. 5,885,802 (high methionine), U.S. Pat. No.        5,885,801 (high threonine), U.S. Pat. No. 6,664,445 (plant amino        acid biosynthetic enzymes), U.S. Pat. No. 6,459,019 (increased        lysine and threonine), U.S. Pat. No. 6,441,274 (plant tryptophan        synthase beta subunit), U.S. Pat. No. 6,346,403 (methionine        metabolic enzymes), U.S. Pat. No. 5,939,599 (high sulfur), U.S.        Pat. No. 5,912,414 (increased methionine), WO98/56935 (plant        amino acid biosynthetic enzymes), WO98/45458 (engineered seed        protein having higher percentage of essential amino acids),        WO98/42831 (increased lysine), U.S. Pat. No. 5,633,436        (increasing sulfur amino acid content), U.S. Pat. No. 5,559,223        (synthetic storage proteins with defined structure containing        programmable levels of essential amino acids for improvement of        the nutritional value of plants), WO96/01905 (increased        threonine), WO95/15392 (increased lysine), US Patent Application        Publication Number 2003/0163838, US Patent Application        Publication Number 2003/0150014, US Patent Application        Publication Number 2004/0068767, U.S. Pat. No. 6,803,498,        WO01/79516, and WO00/09706 (Ces A: cellulose synthase), U.S.        Pat. No. 6,194,638 (hemicellulose), U.S. Pat. No. 6,399,859 and        US Patent Application Publication Number 2004/0025203 (UDPGdH),        U.S. Pat. No. 6,194,638 (RGP).        4. Genes that confer male sterility

There are several methods of conferring genetic male sterilityavailable, such as multiple mutant genes at separate locations withinthe genome that confer male sterility, as disclosed in U.S. Pat. Nos.4,654,465 and 4,727,219 to Brar, et al., and chromosomal translocationsas described by Patterson in U.S. Pat. Nos. 3,861,709 and 3,710,511. Inaddition to these methods, Albertsen, et al., U.S. Pat. No. 5,432,068,describes a system of nuclear male sterility which includes: identifyinga gene which is critical to male fertility; silencing this native genewhich is critical to male fertility; removing the native promoter fromthe essential male fertility gene and replacing it with an induciblepromoter; inserting this genetically engineered gene back into theplant; and thus creating a plant that is male sterile because theinducible promoter is not “on” resulting in the male fertility gene notbeing transcribed. Fertility is restored by inducing, or turning “on,”the promoter, which in turn allows the gene that confers male fertilityto be transcribed.

-   -   A. A dominant nuclear gene, Ms(tc) controlling male sterility.        See, Elkonin, L. A., Theor. Appl. Genet. (2005) 111(7):        1377-1384.    -   B. A tapetum-specific gene, RTS, a sorghum anther-specific gene        is required for male fertility and its promoter sequence directs        tissue-specific gene expression in different plant species. Luo,        Hong, et al., Plant Molecular Biology., 62(3): 397-408(12)        (2006). Introduction of a deacetylase gene under the control of        a tapetum-specific promoter and with the application of the        chemical N—Ac-PPT. See International Publication No. WO        01/29237.    -   C. Introduction of various stamen-specific promoters.        Anther-specific promoters which are of particular utility in the        production of transgenic male-sterile monocots and plants for        restoring their fertility. See, U.S. Pat. No. 5,639,948. See        also, International Publication Nos. WO 92/13956 and WO        92/13957.    -   D. Introduction of the barnase and the barstar genes. See, Paul,        et al., Plant Mol. Biol., 19:611-622 (1992).        -   For additional examples of nuclear male and female sterility            systems and genes, see also, U.S. Pat. Nos. 5,859,341,            6,297,426, 5,478,369, 5,824,524, 5,850,014, and 6,265,640.            See also, Hanson, Maureen R., et al., “Interactions of            Mitochondrial and Nuclear Genes That Affect Male Gametophyte            Development,” Plant Cell., 16:S154-S169 (2004), all of which            are hereby incorporated by reference.    -   A. Modification of RNA editing within mitochondrial open reading        frames. See, Pring, D. R., et al, Curr. Genet. (1998) 33(6):        429-436; Pring, D. R., et al., J. Hered. (1999) 90(3): 386-393;        Pring, D. R., et al., Curr. Genet. (2001) 39(5-6): 371-376; and        Hedgcoth, C., et al., Curr. Genet. (2002) 41(5): 357-365.    -   B. Cytoplasmic male sterility (CMS) from mutations at atp6        codons. See, Kempken, F., FEBS. Lett. (1998): 441(2): 159-160.    -   C. Inducing male sterility through heat shock. See, Wang, L., Yi        Chuan Xue Bao. (2000) 27(9): 834-838.    -   D. Inducing male sterility through treatment of streptomycin on        sorghum callus cultures. See, Elkonin, L. A., et al.,        Genetica (2008) 44(5): 663-673.        5. Transgenes That Confer Tolerance to A Herbicide, For Example:

(A) A herbicide that inhibits the growing point or meristem, such as animidazolinone or a sulfonylurea. Exemplary genes in this category codefor mutant acetolactate synthase (ALS) and acetohydroxyacid synthase(AHAS) enzyme as described, for example, in U.S. Pat. Nos. 5,605,011;5,013,659; 5,141,870; 5,767,361; 5,731,180; 5,304,732; 4,761,373;5,331,107; 5,928,937; and 5,378,824; US Patent Publication No.20070214515, and international publication WO 96/33270.

(B) Glyphosate (tolerance imparted by mutant5-enolpyruvl-3-phosphikimate synthase (EPSP) and aroA genes,respectively) and other phosphono compounds such as glufosinate(phosphinothricin acetyl transferase (PAT) and Streptomyceshygroscopicus phosphinothricin acetyl transferase (bar) genes), andpyridinoxy or phenoxy proprionic acids and cyclohexones (ACCaseinhibitor-encoding genes). See, for example, U.S. Pat. No. 4,940,835,which discloses the nucleotide sequence of a form of EPSPS which canconfer glyphosate tolerance. U.S. Pat. No. 5,627,061 also describesgenes encoding EPSPS enzymes. See also U.S. Pat. Nos. 6,566,587;6,338,961; 6,248,876 B1; 6,040,497; 5,804,425; 5,633,435; 5,145,783;4,971,908; 5,312,910; 5,188,642; 4,940,835; 5,866,775; 6,225,114 B1;6,130,366; 5,310,667; 4,535,060; 4,769,061; 5,633,448; 5,510,471; Re.36,449; RE 37,287 E; and 5,491,288; and international publicationsEP1173580; WO 01/66704; EP1173581 and EP1173582.

Glyphosate tolerance is also imparted to plants that express a gene thatencodes a glyphosate oxido-reductase enzyme as described more fully inU.S. Pat. Nos. 5,776,760 and 5,463,175. In addition glyphosate tolerancecan be imparted to plants by the over expression of genes encodingglyphosate N-acetyltransferase. See, for example, US2004/0082770;US2005/0246798; and US2008/0234130. A DNA molecule encoding a mutantaroA gene can be obtained under ATCC Accession No. 39256, and thenucleotide sequence of the mutant gene is disclosed in U.S. Pat. No.4,769,061. European Patent Application No. 0 333 033 and U.S. Pat. No.4,975,374 disclose nucleotide sequences of glutamine synthetase geneswhich confer tolerance to herbicides such as L-phosphinothricin. Thenucleotide sequence of a phosphinothricin-acetyl-transferase gene isprovided in European Patent Nos. 0 242 246 and 0 242 236. See also, U.S.Pat. Nos. 5,969,213; 5,489,520; 5,550,318; 5,874,265; 5,919,675;5,561,236; 5,648,477; 5,646,024; 6,177,616 B1; and 5,879,903. Exemplarygenes conferring resistance to phenoxy propionic acids,cyclohexanediones and cyclohexones, such as sethoxydim and haloxyfop,are the Acc1-S1, Acc1-S2 and Acc1-S3 genes described by Marshall et al.,Theor. Appl. Genet. 83: 435 (1992).

(C) A herbicide that inhibits photosynthesis, such as a triazine (psbAand gs+ genes) and a benzonitrile (nitrilase gene) such as bromoxynil.Przibilla et al., Plant Cell 3: 169 (1991), describe the transformationof Chlamydomonas with plasmids encoding mutant psbA genes. Nucleotidesequences for nitrilase genes are disclosed in U.S. Pat. No. 4,810,648to Stalker, and DNA molecules containing these genes are available underATCC Accession Nos. 53435, 67441 and 67442. Cloning and expression ofDNA coding for a glutathione S-transferase is described by Hayes et al.,Biochem. J. 285: 173 (1992).

(D) Other genes that confer tolerance to herbicides include: a geneencoding a chimeric protein of rat cytochrome P4507A1 and yeastNADPH-cytochrome P450 oxidoreductase (Shiota et al. (1994) Plant Physiol106:17), genes for glutathione reductase and superoxide dismutase (Aonoet al. (1995) Plant Cell Physiol 36:1687, and genes for variousphosphotransferases (Datta et al. (1992) Plant Mol Biol 20:619).

(E) A herbicide that inhibits protoporphyrinogen oxidase (protox or PPO)is necessary for the production of chlorophyll, which is necessary forall plant survival. The protox enzyme serves as the target for a varietyof herbicidal compounds. PPO-inhibitor herbicides can inhibit growth ofall the different species of plants present, causing their totaldestruction. The development of plants containing altered protoxactivity which are tolerant to these herbicides are described, forexample, in U.S. Pat. Nos. 6,288,306 B1; 6,282,837 B1; and 5,767,373;and international patent publication WO 01/12825.

(F) Dicamba (3,6-dichloro-2-methoxybenzoic acid) is an organochloridederivative of benzoic acid which functions by increasing plant growthrate such that the plant dies.

6. Transgenes That Confer Resistance to Insects or Disease and ThatEncode, For Example:

(A) Plant disease resistance genes. Plant defenses are often activatedby specific interaction between the product of a disease resistance gene(R) in the plant and the product of a corresponding avirulence (Avr)gene in the pathogen. A plant variety can be transformed with clonedresistance gene to engineer plants that are resistant to specificpathogen strains. See, for example Jones et al., Science 266: 789 (1994)(cloning of the tomato Cf-9 gene for resistance to Cladosporium fulvum);Martin et al., Science 262: 1432 (1993) (tomato Pto gene for resistanceto Pseudomonas syringae pv. tomato encodes a protein kinase); Mindrinoset al., Cell 78: 1089 (1994) (Arabidopsis RSP2 gene for resistance toPseudomonas syringae), McDowell and Woffenden, (2003) Trends Biotechnol.21(4): 178-83 and Toyoda et al., (2002) Transgenic Res. 11(6):567-82. Aplant resistant to a disease is one that is more resistant to a pathogenas compared to the wild type plant.

(B) A Bacillus thuringiensis protein, a derivative thereof or asynthetic polypeptide modeled thereon. See, for example, Geiser et al.,Gene 48: 109 (1986), who disclose the cloning and nucleotide sequence ofa Bt delta-endotoxin gene. Moreover, DNA molecules encodingdelta-endotoxin genes can be purchased from American Type CultureCollection (Rockville, Md.), for example, under ATCC Accession Nos.40098, 67136, 31995 and 31998. Other non-limiting examples of Bacillusthuringiensis transgenes being genetically engineered are given in thefollowing patents and patent applications: U.S. Pat. Nos. 5,188,960;5,689,052; 5,880,275; 5,986,177; 7,105,332; 7,208,474; WO 91/14778; WO99/31248; WO 01/12731; WO 99/24581; WO 97/40162 and U.S. applicationSer. Nos. 10/032,717; 10/414,637; 11/018,615; 11/404,297; 11/404,638;11/471,878; 11/780,501; 11/780,511; 11/780,503; 11/953,648; and Ser. No.11/957,893.

(C) An insect-specific hormone or pheromone such as an ecdysteroid andjuvenile hormone, a variant thereof, a mimetic based thereon, or anantagonist or agonist thereof. See, for example, the disclosure byHammock et al., Nature 344: 458 (1990), of baculovirus expression ofcloned juvenile hormone esterase, an inactivator of juvenile hormone.

(D) An insect-specific peptide which, upon expression, disrupts thephysiology of the affected pest. For example, see the disclosures ofRegan, J. Biol. Chem. 269: 9 (1994) (expression cloning yields DNAcoding for insect diuretic hormone receptor); Pratt et al., Biochem.Biophys. Res. Comm. 163: 1243 (1989) (an allostatin is identified inDiploptera puntata); Chattopadhyay et al. (2004) Critical Reviews inMicrobiology 30 (1): 33-54 2004; Zjawiony (2004) J Nat Prod 67 (2):300-310; Carlini and Grossi-de-Sa (2002) Toxicon, 40 (11): 1515-1539;Ussuf et al. (2001) Curr Sci. 80 (7): 847-853; and Vasconcelos andOliveira (2004) Toxicon 44 (4): 385-403. See also U.S. Pat. No.5,266,317 to Tomalski et al., who disclose genes encodinginsect-specific toxins.

(E) An enzyme responsible for a hyperaccumulation of a monoterpene, asesquiterpene, a steroid, hydroxamic acid, a phenylpropanoid derivativeor another non-protein molecule with insecticidal activity.

(F) An enzyme involved in the modification, including thepost-translational modification, of a biologically active molecule; forexample, a glycolytic enzyme, a proteolytic enzyme, a lipolytic enzyme,a nuclease, a cyclase, a transaminase, an esterase, a hydrolase, aphosphatase, a kinase, a phosphorylase, a polymerase, an elastase, achitinase and a glucanase, whether natural or synthetic. See PCTapplication WO 93/02197 in the name of Scott et al., which discloses thenucleotide sequence of a callase gene. DNA molecules which containchitinase-encoding sequences can be obtained, for example, from the ATCCunder Accession Nos. 39637 and 67152. See also Kramer et al., InsectBiochem. Molec. Biol. 23: 691 (1993), who teach the nucleotide sequenceof a cDNA encoding tobacco hookworm chitinase, and Kawalleck et al.,Plant Molec. Biol. 21: 673 (1993), who provide the nucleotide sequenceof the parsley ubi4-2 polyubiquitin gene, and U.S. Pat. Nos. 6,563,020;7,145,060 and 7,087,810.

(G) A molecule that stimulates signal transduction. For example, see thedisclosure by Botella et al., Plant Molec. Biol. 24: 757 (1994), ofnucleotide sequences for mung bean calmodulin cDNA clones, and Griess etal., Plant Physiol. 104: 1467 (1994), who provide the nucleotidesequence of a maize calmodulin cDNA clone.

(H) A hydrophobic moment peptide. See PCT application WO 95/16776 andU.S. Pat. No. 5,580,852 disclosure of peptide derivatives of Tachyplesinwhich inhibit fungal plant pathogens) and PCT application WO 95/18855and U.S. Pat. No. 5,607,914 (teaches synthetic antimicrobial peptidesthat confer disease resistance).

(I) A membrane permease, a channel former or a channel blocker. Forexample, see the disclosure by Jaynes et al., Plant Sci. 89: 43 (1993),of heterologous expression of a cecropin-beta lytic peptide analog torender transgenic tobacco plants resistant to Pseudomonas solanacearum.

(J) A viral-invasive protein or a complex toxin derived therefrom. Forexample, the accumulation of viral coat proteins in transformed plantcells imparts resistance to viral infection and/or disease developmenteffected by the virus from which the coat protein gene is derived, aswell as by related viruses. See Beachy et al., Ann. Rev. Phytopathol.28: 451 (1990). Coat protein-mediated resistance has been conferred upontransformed plants against alfalfa mosaic virus, cucumber mosaic virus,tobacco streak virus, potato virus X, potato virus Y, tobacco etchvirus, tobacco rattle virus and tobacco mosaic virus. Id.

(K) An insect-specific antibody or an immunotoxin derived therefrom.Thus, an antibody targeted to a critical metabolic function in theinsect gut would inactivate an affected enzyme, killing the insect. Cf.Taylor et al., Abstract #497, SEVENTH INT'L SYMPOSIUM ON MOLECULARPLANT-MICROBE INTERACTIONS (Edinburgh, Scotland, 1994) (enzymaticinactivation in transgenic tobacco via production of single-chainantibody fragments).

(L) A virus-specific antibody. See, for example, Tavladoraki et al.,Nature 366: 469 (1993), which shows that transgenic plants expressingrecombinant antibody genes are protected from virus attack.

(M) A developmental-arrestive protein produced in nature by a pathogenor a parasite. Thus, fungal endo alpha-1,4-D-polygalacturonasesfacilitate fungal colonization and plant nutrient release bysolubilizing plant cell wall homo-alpha-1,4-D-galacturonase. See Lamb etal., Bio/Technology 10: 1436 (1992). The cloning and characterization ofa gene which encodes a bean endopolygalacturonase-inhibiting protein isdescribed by Toubart et al., Plant J. 2: 367 (1992).

(N) A developmental-arrestive protein produced in nature by a plant. Forexample, Logemann et al., Bio/Technology 10: 305 (1992), have shown thattransgenic plants expressing the barley ribosome-inactivating gene havean increased resistance to fungal disease.

(O) Genes involved in the Systemic Acquired Resistance (SAR) Responseand/or the pathogenesis related genes. Briggs, S., Current Biology, 5(2)(1995), Pieterse and Van Loon (2004) Curr. Opin. Plant Bio. 7(4):456-64and Somssich (2003) Cell 113(7):815-6.

(P) Antifungal genes (Cornelissen and Melchers, Pl. Physiol.101:709-712, (1993) and Parijs et al., Planta 183:258-264, (1991) andBushnell et al., Can. J. of Plant Path. 20(2):137-149 (1998). Also seeU.S. application Ser. Nos. 09/950,933; 11/619,645; 11/657,710;11/748,994; 11/774,121 and U.S. Pat. Nos. 6,891,085 and 7,306,946.

(Q) Detoxification genes, such as for fumonisin, beauvericin,moniliformin and zearalenone and their structurally related derivatives.For example, see U.S. Pat. Nos. 5,716,820; 5,792,931; 5,798,255;5,846,812; 6,083,736; 6,538,177; 6,388,171 and 6,812,380.

(R) Cystatin and cysteine proteinase inhibitors. See U.S. Pat. No.7,205,453.

(S) Defensin genes. See WO03000863 and U.S. Pat. Nos. 6,911,577;6,855,865; 6,777,592 and 7,238,781.

(T) Genes conferring resistance to nematodes. See e.g. PCT ApplicationWO96/30517; PCT Application WO93/19181, WO 03/033651 and Urwin et al.,Planta 204:472-479 (1998), Williamson (1999) Curr Opin Plant Bio.2(4):327-31; and U.S. Pat. Nos. 6,284,948 and 7,301,069.

(U) Genes that confer resistance to Phytophthora Root Rot, such as theRps 1, Rps 1-a, Rps 1-b, Rps 1-c, Rps 1-d, Rps 1-e, Rps 1-k, Rps 2, Rps3-a, Rps 3-b, Rps 3-c, Rps 4, Rps 5, Rps 6, Rps 7 and other Rps genes.See, for example, Shoemaker et al, Phytophthora Root Rot Resistance GeneMapping in Soybean, Plant Genome IV Conference, San Diego, Calif.(1995).

(V) Genes that confer resistance to Brown Stem Rot, such as described inU.S. Pat. No. 5,689,035.

(W) Genes that confer resistance to Colletotrichum, such as described inUS Patent publication US20090035765. This includes the Rcg locus thatmay be utilized as a single locus conversion.

Seed Treatments and Cleaning

Another embodiment of this invention is the method of harvesting theseed of the maize variety PH2877MR as seed for planting. Embodimentsinclude cleaning the seed, treating the seed, and/or conditioning theseed. Cleaning the seed includes removing foreign debris such as weedseed and removing chaff, plant matter, from the seed. Conditioning theseed can include controlling the temperature and rate of dry down andstoring seed in a controlled temperature environment. Seed treatment isthe application of a composition to the seed such as a coating orpowder. Methods for producing a treated seed include the step ofapplying a composition to the seed or seed surface. Some examples ofcompositions are insecticides, fungicides, pesticides, antimicrobials,germination inhibitors, germination promoters, cytokinins, andnutrients.

To protect and to enhance yield production and trait technologies, seedtreatment options can provide additional crop plan flexibility and costeffective control against insects, weeds and diseases, thereby furtherenhancing the invention described herein. Seed material can be treated,typically surface treated, with a composition comprising combinations ofchemical or biological herbicides, herbicide safeners, insecticides,fungicides, germination inhibitors and enhancers, nutrients, plantgrowth regulators and activators, bactericides, nematicides, avicidesand/or molluscicides. These compounds are typically formulated togetherwith further carriers, surfactants or application-promoting adjuvantscustomarily employed in the art of formulation. The coatings may beapplied by impregnating propagation material with a liquid formulationor by coating with a combined wet or dry formulation.

Examples of the various types of compounds that may be used as seedtreatments are provided in The Pesticide Manual: A World Compendium, C.D. S. Tomlin Ed., Published by the British Crop Production Council,which is hereby incorporated by reference. Some seed treatments that maybe used on crop seed include, but are not limited to, one or more ofabscisic acid, acibenzolar-S-methyl, avermectin, amitrol, azaconazole,azospirillum, azadirachtin, azoxystrobin, Bacillus spp. (including oneor more of cereus, firmus, megaterium, pumilis, sphaericus, subtilisand/or thuringiensis), Bradyrhizobium spp. (including one or more ofbetae, canariense, elkanii, iriomotense, japonicum, liaonigense,pachyrhizi and/or yuanmingense), captan, carboxin, chitosan,clothianidin, copper, cyazypyr, difenoconazole, etidiazole, fipronil,fludioxonil, fluoxastrobin, fluquinconazole, flurazole, fluxofenim,harpin protein, imazalil, imidacloprid, ipconazole, isoflavenoids,lipo-chitooligosaccharide, mancozeb, manganese, maneb, mefenoxam,metalaxyl, metconazole, myclobutanil, PCNB, penflufen, penicillium,penthiopyrad, permethrine, picoxystrobin, prothioconazole,pyraclostrobin, rynaxypyr, S-metolachlor, saponin, sedaxane, TCMTB,tebuconazole, thiabendazole, thiamethoxam, thiocarb, thiram,tolclofos-methyl, triadimenol, trichoderma, trifloxystrobin,triticonazole and/or zinc. PCNB seed coat refers to EPA registrationnumber 00293500419, containing quintozen and terrazole. TCMTB refers to2-(thiocyanomethylthio) benzothiazole.

Seed varieties and seeds with specific transgenic traits may be testedto determine which seed treatment options and application rates maycomplement such varieties and transgenic traits in order to enhanceyield. For example, a variety with good yield potential but head smutsusceptibility may benefit from the use of a seed treatment thatprovides protection against head smut, a variety with good yieldpotential but cyst nematode susceptibility may benefit from the use of aseed treatment that provides protection against cyst nematode, and soon. Likewise, a variety encompassing a transgenic trait conferringinsect resistance may benefit from the second mode of action conferredby the seed treatment, a variety encompassing a transgenic traitconferring herbicide resistance may benefit from a seed treatment with asafener that enhances the plants resistance to that herbicide, etc.Further, the good root establishment and early emergence that resultsfrom the proper use of a seed treatment may result in more efficientnitrogen use, a better ability to withstand drought and an overallincrease in yield potential of a variety or varieties containing acertain trait when combined with a seed treatment.

Uses of Sorghum

Sorghum is used as livestock feed, as sugar or grain for humanconsumption, as biomass, and as raw material in industry. Sorghum graincan be used as livestock feed, such as to beef cattle, dairy cattle,hogs and poultry. In some embodiments, the plant is used as livestockfeed in the form of fodder, silage, hay and pasture. In someembodiments, commodity plant products produced from hybrid seed such asfood, feed, forage, and syrup are provided.

Provided are uses of sorghum in the form of bread, porridge,confectionaries and as an alcoholic beverage. Grain sorghum may beground into flour and either used directly or blended with wheat or cornflour in the preparation of food products. In addition to directconsumption of the grain, sorghum has long been used in many areas ofthe world to make beer. The uses of sorghum, in addition to humanconsumption of kernels, include both products of dry and wet millingindustries. The principal products of sorghum dry milling are grits,meal and flour. Starch and other extracts for food use can be providedby the wet milling process.

Also provided are uses of sorghum as an industrial raw material.Industrial uses include sorghum starch from the wet-milling industry andsorghum flour from the dry milling industry. Sorghum starch and flourhave application in the paper and textile industries. Other industrialuses include applications in adhesives, building materials and asoil-well muds. Considerable amounts of sorghum, both grain and plantmaterial, have been used in industrial alcohol production.

Characteristics of PH2877MR

Sorghum line PH2877MR has shown stability for traits listed in Table 1.It has been self-pollinated, bulk increased and checked for uniformityof plant type to assure genetic homozygosity and phenotypic stability.The line has been increased by hand pollination and in isolated fieldplantings with continued observation for uniformity. It has beenobserved to be uniform and stable for at least six generations.

Sorghum line PH2877MR has the characteristics shown in Table 1.

Provided are seed of sorghum line PH2877MR, plants of sorghum linePH2877MR, plant parts of sorghum line PH2877MR, and processes for makinga plant that comprise crossing sorghum line PH2877MR with another plant.In some embodiments, PH2877MR may be provided with cytoplasm comprisinga gene or genes that cause male sterility. Also disclosed are processesfor making a plant containing in its genetic material one or more traitsintrogressed into PH2877MR through backcross conversion and/ortransformation, and to the seed, plant and plant arts produced thereby.Hybrid sorghum seed, plant, or plant part produced by crossing the linePH2877MR or a locus conversion of PH2877MR with another plant are alsoprovided.

The terms variants, modification and mutant refer to a hybrid or inbredseed or a plant produced by that hybrid or inbred seed which isphenotypically similar to PH2877MR.

The foregoing discovery has been described in detail by way ofillustration and example for purposes of exemplification. However, itwill be apparent that changes and modifications such as single genemodifications and mutations, somaclonal variants, variant individualsselected from populations of the plants of the instant variety, and thelike, are considered to be within the scope of the present discovery.All references disclosed herein whether to journal, patents, publishedapplications and the like are hereby incorporated in their entirety byreference.

DEPOSIT

Applicant has made a deposit of at least 625 seeds of Sorghum VarietyPH2877MR with the Provasoli-Guillard National Center for Marine Algaeand Microbiota (NCMA), 60 Bigelow Drive, East Boothbay, Me. 04544, USA,with NCMA Accession Number 202110053. The seeds deposited with the NCMAon Oct. 21, 2021 were obtained from the seed of the variety maintainedby Pioneer Hi-Bred International, Inc., 7250 NW 62nd Avenue, Johnston,Iowa, 50131 since prior to the filing date of this application. Accessto this seed will be available during the pendency of the application tothe Commissioner of Patents and Trademarks and persons determined by theCommissioner to be entitled thereto upon request. Upon allowance of anyclaims in the application, the Applicant will make the deposit availableto the public pursuant to 37 C.F.R. § 1.808. This deposit of the SorghumVariety PH2877MR will be maintained in the NCMA depository, which is apublic depository, for a period of 30 years, or 5 years after the mostrecent request, or for the enforceable life of the patent, whichever islonger, and will be replaced if it becomes nonviable during that period.Additionally, Applicant has or will satisfy all of the requirements of37 C.F.R. §§ 1.801-1.809, including providing an indication of theviability of the sample upon deposit. Applicant has no authority towaive any restrictions imposed by law on the transfer of biologicalmaterial or its transportation in commerce. Applicant does not waive anyinfringement of rights granted under this patent or under the PlantVariety Protection Act (7 USC 2321 et seq.).

Breeding History

Inbred PH2877MR was produced by crossing a proprietary non-public inbredwith another proprietary non-public inbred to generate F1 seed. Thedetails of the breeding stages are below.

Detail of Stage

-   -   First cross 2PEGH34R×2PPAC27N    -   F1 was planted, self pollinated and harvested in bulk    -   F2 was grown and harvested in bulk    -   F3 population was planted and grown    -   F4 family was grown head-to-row and heads were selected    -   F5 family was grown head-to-row, heads were selected    -   F6 was grown and heads were selected    -   F7 was grown and heads were selected. No further selection        within the line was practiced

The criteria used for selection were yield per se and yield in hybridcombination. Agonomics traits such as maturity and stalk lodgingresistance were considered as selection criteria during the process.Other selection criteria include: head type, plant height and planttype.

TABLE 1 Variety Descriptions for PH2877MR based on Morphological,Agronomic and Quality Traits Trait Description Kind Sorghum Use Class:grain Days from planting to mid-anthesis 67 Plant Coleoptile red Plantpigment purple Plant height in inches 41 Stalk Height (cm from soil totop of 104.14 panicle) Plant: Natural height of foliage at mediumpanicle emergence Plant: Total height at maturity medium Diameter ofmain stalk mid stout Waxy Bloom present Number of Tillers moderate StemSweetness insipid Stem Juiciness dry (phity) Panicle Exertion shortDegree of Senescence intermediate Leaf Color light green Leaf: Width ofblade of first leaf moderate below flag leaf Leaf margin wavy Leafattitude or erectness erect Ligule present Leaf midrib color (first leafbelow intermediate flag leaf) Panicle Anther Color (at flowering) darkyellow Panicle Length (cm) 30 Panicle Density Semi Compact Panicle Shapeat maturity cylindrical Length of central rachis (% of 0.75 paniclelength) Panicle erectness erect Rachis branches at grain maturity erectRachis Branch Average intermediate Panicle Type more cylindrical sorghumpanicle type Glume length at maturity intermediate Percent of graincovered by the 0.25 glume Glume Texture Intermediate Glume color atgrain maturity black Glume Hairiness or pubescence intermediate GlumeVenation absent Glume Transverse Wrinkle absent Glume Awns long RootsFibrous Grain Testa Absent Grain Mesocarp Thickness intermediate GrainEpicarp Color (Genetic) red Grain Spreader (Tannin in Pericarp) absentGrain Intensifier absent Grain Color (Appearance) light red GrainEndosperm Color white Grain Endosperm Type starchy Grain EndospermTexture floury Grain Seed Shape oval No. of seed per 100 G Genotype 2952

What is claimed is:
 1. A seed of sorghum variety PH2877MR,representative seed of the variety having been deposited under NCMAAccession Number
 202110053. 2. A plant, non-seed plant part, seed orplant cell produced by growing the sorghum variety PH2877MR seed ofclaim
 1. 3. The plant or non-seed plant part of claim 2, comprising apollen or ovule.
 4. The plant, non-seed plant part, seed or plant cellof claim 2, further comprising a locus conversion, wherein the plant ora plant grown from the plant part, seed or plant cell otherwisecomprises all of the physiological and morphological characteristics ofsorghum variety PH2877MR when grown under the same environmentalconditions.
 5. The plant, non-seed plant part, seed, or plant cell ofclaim 4, wherein the locus conversion confers a property selected fromthe group consisting of abiotic stress tolerance, altered phosphatecontent, altered antioxidant content, altered fatty acid profile,altered essential amino acid profile, altered carbohydrate content,herbicide resistance, insect resistance, disease resistance, and salttolerance.
 6. A sorghum seed produced by crossing the plant or non-seedplant part of claim 4 with a different plant.
 7. An F1 hybrid plantproduced by growing the seed of claim
 6. 8. A plant part comprising atleast one cell of the F1 hybrid plant of claim
 7. 9. A method ofproducing a sorghum seed, the method comprising crossing two sorghumplants and harvesting the resultant sorghum seed, wherein at least oneof the sorghum plants is the sorghum plant of claim
 4. 10. A sorghumseed produced by crossing the plant or non-seed plant part of claim 2with a different plant.
 11. An F1 hybrid plant produced by growing theseed of claim
 10. 12. A plant part comprising at least one cell of theF1 hybrid plant of claim
 11. 13. A non-seed plant part produced bygrowing the seed of claim
 10. 14. The F1 hybrid seed of claim 11 furthercomprising a single locus conversion.
 15. A method of producing asorghum seed, the method comprising crossing two sorghum plants andharvesting the resultant sorghum seed, wherein at least one of thesorghum plants is the sorghum plant of claim
 2. 16. A method forproducing a second sorghum plant or plant part, the method comprisingdoubling haploid seed generated from a cross of the plant or non-seedplant part of claim 2 with an inducer variety, thereby producing thesecond sorghum plant or plant part.
 17. A method comprising isolatingnucleic acids from the plant, non-seed plant part, seed or plant cell ofclaim
 2. 18. A method of plant breeding, the method comprising: (a)crossing a plant of sorghum variety PH2877MR with a second plantcomprising a desired single locus to produce F1 progeny plants,representative seed of said sorghum variety PH2877MR having beendeposited under NCMA Accession Number 202110053; (b) selecting at leasta first progeny plant from step (a) that comprises the single locus toproduce a selected progeny plant; (c) crossing the selected progenyplant from step (b) with a plant of sorghum variety PH2877MR to producea backcross progeny plant that comprises the single locus.
 19. A plant,non-seed plant part, seed, or plant cell of sorghum variety PH2877MR,representative seed of the variety having been deposited under NCMAAccession Number 202110053, the plant, non-seed plant part, seed, orplant cell further comprising a single locus conversion, wherein thesingle locus conversion is introduced into sorghum variety PH2877MR bybackcrossing or transformation.
 20. The plant, plant part, seed, orplant cell of claim 19, wherein the locus conversion confers a propertyselected from the group consisting of abiotic stress tolerance, alteredphosphate content, altered antioxidant content, altered fatty acidprofile, altered essential amino acid profile, altered carbohydratecontent, herbicide resistance, insect resistance, disease resistance,and salt tolerance.